Synergistic Research GCT's?

Anyone have experience with synergistic research's GCTs? My room and speakers are outfitted with the full HFT set up and I have a couple of PHT's on my TT. The sound is marvelous. Also interested in the ECT's and GCT's. I've read plenty of info about the ECT's but there seems to be none about the GCT's.
I'm running multiple sets of PHT, ECT and a full room/speaker treatment of the HFTs. I've tried these things everywhere and even x-rayed and studied how they're built. About the only thing I don't know is what it is they put inside. Its different in different versions. So they vary the size, shape and inner material to tune for different applications. Yet as you know they all produce about the same result. (Notable exception for PHT versions.)

Also have a lot of Synergistic not only now but over 30 years experience building my system. This includes experience with their ground plane tech as well as a lot of other stuff I've tried with grounding.

So no direct experience with GCT but 30 years that tells me GCT is gonna be about the same as all the rest. Also, easy way to test it out, try putting an ECT or two in the locations where GCT would go. If you pull ECT from one component and move it to a GCT location and the sound doesn't get much worse that's a pretty good indication. Because they all work about the same, then if ECT works there you can be sure GCT will work there and at least as good.

I suspect the reason there's hardly any info is these things are a hard enough sell in the first place. Many find it just too hard to believe these things work at all, let alone that they work better than just about anything else. Its even harder to believe anything stuck to just a ground can make any difference. Well, it does. I just haven't gotten around to trying this particular one yet. So many tweaks... so little time... 
Sorry, read your post again, thought you had ECT. Definitely get ECT. They work on everything (read my review) and each one has about the same magnitude effect as HFT or PHT. In other words just one is noticeable, a full set impressive. Don't waste time opening components to stick them on inside. It seems they would work better there but they work just as well on the outside, and its a whole lot easier to move one around and find where it works the best. Check out my system to see where I'm using mine.
On more careful reading I see one of the results of using GCT's is a warmer sound. I don't like warm. So acquiring GCT's has been scratched from my list. I'm so mesmerized with the way my system sounds now I'm in no hurry to buy the ECT's. New plan, sell a few things then purchase the ECT's. In the meantime I'll be enjoying my music.